Function: DateDiff()
Purpose: The DateDiff() function returns the difference between two dates.
Usage: DateDiff(interval, date1, date2)
Interval may be set to:
yyyy for year
q for quarter
m for month
y for day of year
d for day
w for weekday
ww for week
h for hour
n for minute
s for second
Returns: Number of intervals between date1 and date2.
Examples and Special Cases
DateDiff("yyyy", "6-Nov-2006", "7-Nov-2006") returns 0
DateDiff("yyyy", "31-Dec-2006", "1-Jan-2007") returns 1
DateDiff("d", "6-Nov-2006", "8-Nov-2006") returns 2
